Millwood, 36, pitched for the Baltimore Orioles last season, going 4-16 with a 5.10 ERA. He opted out of his minor-league contract with the New York Yankees earlier this month after going 2-1 with a 4.50 ERA between Double- and Triple-A.

Lackey's disabled-list stint is considered to be precautionary, while Matsuzaka’s situation appears much more bleak.

An MRI Wednesday revealed the sprain in his ulnar collateral ligament and he is not expected to touch a ball for four weeks, then will likely have at least a month of rehabilitation before making his way back to Fenway.

The pitcher was set to get a second opinion on his elbow at the encouragement of the club.

The Chicago Cubs were also reportedly pursuing Millwood, as were the Los Angeles Angels, but are since said to have lost interest.